| 摘要 |
A wide-angle zoom lens is formed of a first lens group having a negative refractive power, a stop, and a second lens group having a positive refractive power. Magnification is varied by moving the second lens group to the object side when zooming from the wide-angle end to the telephoto end. What would otherwise be a shift of the image plane with the zooming is corrected by moving the first lens group to the image side when zooming from the wide-angle end to the telephoto end. A lens in the second lens group has at least one surface that is aspherical and is positioned on the image side of a lens in the second lens group having positive refractive power and a convex surface on the object side.
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